What's This Screeching Sound & Why Does it Occur?

Upgrading a PC's memory resulted in screeching sounds whenever it tried to play audio. Has this ever happened to you?

Last week, I helped my father-in-law's friend by upgrading her PC's memory from 2 Gbytes to 4 Gbytes. Simple, right? I've done memory upgrades many times on both desktop and laptop PCs without incident, but not this time. Why did this bizarre side effect occur?

The PC in question is an HP/Compaq dc5750 desktop unit. It originally ran Windows XP but was upgraded to Windows 7 by a local computer dealer. It has 2 Gbytes of DDR2 RAM. It runs decently, but would surely run faster with 4 Gbytes. After three visits in four days, I ended up restoring the PC's original memory. Here's what happened.

On the first visit, (Thursday) I documented the PC's existing memory. Figure 1 shows the PC.

Figure 1. The PC in need of an upgrade: An HP dc5750 Microtower

After opening the PC, I found four 512 Gbyte DDR2 memory modules, removed one, and photographed it before reinserting it and closing the case.

The local Best Buy doesn't carry DDR2 memory, but fortunately, I found what I needed at Micro Center. Returning on Saturday with two 2 Gbyte DDR modules, I expected things to go smoothly. Silly me.

After replacing the four 512 GB modules with the two 2 Gbyte modules, I started the PC. It booted normally after I confirmed that the BIOS correctly identified the new memory. But, there was an unexplained wide effect: Whenever Windows made a sound, it literally screeched. Listen to the sound, if you dare. It should sound like the familiar windows chime.

While the PC did work, the screeching was too annoying. Yes, I could have set all windows sounds to off, but that's not the point. So, I removed the new memory and reinstalled the old modules.

Thinking that perhaps one of the modules was defective, I returned the first set to Micro Center and tried modules from a different manufacturer, which cost $5 more per module. Figure 3 shows one of modules.

Figure 3. Here's one of the two second-try memory modules.

Figure 4 shows the package.

Figure 4. According to the packaging, this memory module should be compatible with the PC.

The second pair of memory modules (installed on Sunday) produced the same screeching sounds as with the first. So once again, I set the back to its original 2 Gbytes of memory and will return the second set to Micro Center.

I've never seen nor heard of such strange symptoms. Have you? Did I miss something? Please let me know what else to try.

As for "get a new computer," This is the new computer. The user is quite elderly, though quite perky for her age. Her previous computer was giving some trouble and went to a local computer shop for an upgrade from Vista to Win7. The technician at the shop said it needed a new power supply and so the cost of a newer used PC with Win7 was less that the estimate for the repair. So, I ended up with the older PC, which had a scant 512MB on it. So, she bought her current PC.

Have you ever seen Win7 with 512MB? Trust me, you don't want to see how slow it is. So, I increased the memory to 4GB and it runs quite well. I used it for about a year as my wife's PC at home to get her used to Win7 and off XP, then we bought her a new Win7 PC for her office, then a Win10 PC (same HP hardware) for home. The upgraded old PC is in the closet, but it's a good backup if needed.

The user of the AMD PC was dissappointed with Win7 because Microsoft took away her Freecell Solitare game, replacing it with an online version. I managed to find an offline version and isntalled it. She's very happy because the online version wasn't an option with her dialup internet. The online game would cause her to tie up her phone line.

I looked into DSL but it's not avilable at her home, only cable or Verizon FiOS (around $70/month), neither if which she will pay for so she stays with her $10/month dialup.

Martin... " I found 1 GB DIMMs online at $17 each, but then need four of them. Total $68. "

That seems expensive. I found mine here - A$ 27 (=US$ 20) for four x 2GB. However there is a note: "Buyer note: it is hgih density, Only fit for AMD Motherboard. It can not support any intel"

As I recall my MB was Intel but the manual did specify DDR2. I Actually discussed it with one of our IT gurus before buying them and he said there is only DDR2 - not AMD DDR2 and INTEL DDR2. But maybe this is why I got the only half available problem. Do you know if the MB you are dealing with is Intel or AMD? I'm sure my IT Guru's advice to you would be the same as he gave me - "Get a new computer, Dave..."

Remember the good old days when SIMMs only had 30 pins and the only thing you had to worry about was how many KB / MB they had?? :-)

I installed 4x1GB DDR2 modules. No difference. Same audio problem so I put hte 4x512MB modules back in and will return the 1 GB modules. At one point, I had disabled the audio driver because she doesn't use sound at all. In the end Grandpa and friend really wanted to add memory thinking that family photos sent by e-mail would load faster. But the internet connectin is dialup. The only way for images to load faster is with a fester connection, but that costs money. DSL is not avilable at that location, only cable and FiOS, but they cost too much.

@JGrubbs thanks for chiming in on this. My processor is an Intel Q6600 and the OS is Win 7 Professional, both 64 bit apparently, so still does not make sense (to me, anyway :-).... could you comment further? Thanks for the tip about the Ram Disk....I remember setting something like that up in the dim and distant past, maybe with DOS on top of its 640K limit? How do you do that in Windows - is it in the OS or do you have to get another program to do that?

WIN 7 32 bit version addresses only 4 GB , WIN 7 64 bit addresses 8, 16, or 192 GB depending on which version ( Home Basic, Home Premimum or Professional). You can set up a RamDisk with the other 4 GB for pagefile and other temporary files.

Martin I had a similar upgrade not too long ago on my Win 7 PC. I think much the same kind of memory (DDR2). It said it could take up to 8GB of RAM, so I purchased 4 x 2GB sticks. It works, but only 4 GB appears on the POST message, and is usable. The strange thing is that if you look in my computer / System Properties, it says 8.00 GB (4.00 GB Usable). If it knows it's there, why can't it use it? 4GB is better than the 2GB I had before, so I live with it.

Old story....to err is human, to really foul things up takes a computer....

Do the sounds only come from the speaker or the power supply? If the switching supply were struggling with the new memory and the switching rate were in the audible range then that could account for the noise. Not sure why a sound board and such would start screeching unless the supply were taxed and you now have more supply ripple with the heavier load.

As a precaution leave your cell phone on the other side of the room. My older PC freaks out when the phone causes my speakers to chirp and pop.